The word Adagio, literally 'at ease', and then 'slow' or even 'cautious', has had various musical meanings, with eighteenth century argument as to the relative degree of slowness implied by the term. For many, including Mozart, however, Adagio was a generic word to signify a slow movement, the necessary lyrical relaxation of tension to be provided as a second or third movement in a work of three or four movements.

The Baroque period provides moving examples of the slow, aria type movement, often an extended and more or less embellished melody over an accompanying texture. Georg Philipp Telemann, preferred in his time to his slightly younger contemporary Johann Sebastian Bach, had in 1721 established himself as director of music in the city churches of Hamburg, where he remained until his death in 1767, to be succeeded there by his godson Carl Philipp Emanuel Bach, second son of Johann Sebastian. Telemann was prolific and versatile and his compositions included music sacred and secular, with 46 Passion settings and 1043 cantatas in addition to operas, songs and instrumental works in some abundance. His Trumpet Concerto in D major, one of 47 solo concertos for a variety of instruments, is in the expected three movement form, relaxing in its second movement into a more lyrical mood, time for the trumpeter to draw breath.

Johann Sebastian Bach started his musical career as an organist, from 1708 to 1717 at the court of Duke Ernst of Weimar, moving thereafter to a position as Court Kapellmeister at Cöthen and then, in 1723, to Leipzig as Thomascantor, with responsibility for the music of the principal city churches. At Weimar Bach served as court organist and it was natural that he should at this time write a number of works for the organ. The Toccata, Adagio and Fugue in C major belongs to this period and reflects in its form the standard Italian solo concerto, with the Adagio forming an aria second movement. The Concerto for Violin and Oboe belongs to the period of Bach's employment at Cöthen. It was arranged, some ten years or so later, as a concerto for two harpsichords, to be played with the Leipzig University Collegium musicum, in common with other instrumental concertos of the Cöthen period. It has been re-transcribed into its original form, providing interplay between the two contrasted solo instruments for which it was originally conceived.

It was said that Mozart had no great liking for the flute. Whatever his natural inclinations, he provided superb music for the instrument, notably in response to a commission arranged for him in Mannheim. In 1777, tired of the restrictions and limitations of Salzburg, where, like his father, he was in the service of the ruling Archbishop, Mozart set out to seek a better fortune elsewhere. Mannheim, the then capital of the Elector Palatine, boasted one of the finest musical establishments in Europe and it was here that he was asked by the German-born amateur flautist Ferdinand De Jean, a surgeon with the Dutch East India Company, to write for him three short, simple concertos and two quartets for the flute. The full commission was never fulfilled, but Mozart did produce two concertos and two quartets. The first of the two concertos, an original work, seemingly unlike its companion, offers, in its slow movement, music of particular charm and poignancy.

Mozart acknowledged a debt to his older contemporary, Joseph Haydn, particularly in the string quartets he wrote during the last ten years ot his life in Vienna. Haydn acknowledged a similar reciprocal debt to Mozart, whose gifts and way of life differed so markedly from his own. Haydn spent the greater part of his long career in the service of the Esterházy family, occupied by regular composition for the forces at his disposal, performance of these and other works and administration of the Esterházy musical establishment, in all its details. Unlike Mozart, who was distinguished as a performer, Haydn wrote relatively few concertos. His Cello Concerto in D major, one of two such works that survive, was written in the early 1760s, before the completion of the new Esterházy palace at Esterháza, for Anton Kraft, principal cellist with the Esterházy Kapelle until it was dissolved in 1790. The A major slow movement is in the form of an aria for solo cello, accompanied here by oboes and strings.

A man of many talents, Felix Mendelssohn was precocious and prolific as a performer and as a composer. He completed the second of his two numbered piano concertos, the Concerto in D minor, in 1837, partly during his honeymoon, preceding his move to Leipzig as conductor of the Gewandhaus Orchestra in the autumn of that year. He appeared as soloist in the first performance of the work in Birmingham, where he directed the Music Festival in September. The solo piano opens the central B flat major Adagio and remains the centre of interest throughout the movement.

Schubert had written his great C major Quintet nine years earlier, in 1828, the last year of his life. Unlike the string quintets of Mozart, which use two violas, Schubert's work is scored for two cellos, like the quintets of Boccherini. The E major second movement Adagio breathes a spirit of serenity that it would be difficult to match, accompanied at first by the plucked notes of the second cello, before the tranquillity is broken by a turbulent F minor section, music that has its echoes even when the key and mood of the opening is restored.

The violinist, conductor and composer Louis Spohr was 25 and already enjoying a distinguished career when Mendelssohn was born in 1809 and was to outlive the younger man by a dozen years. The first of his concertos for the clarinet, an instrument that had been developed relatively recently, finding its place in the Vienna Court Orchestra only in 1787, was written in 1808 for the virtuoso Johann Simon Hermstedt, director of music to the Duke of Sondershausen, who commissioned the work. The concerto has a central movement of peaceful lyricism, an extended aria, accompanied only by strings.

The name of Franz Berwald may not be so familiar outside his native Sweden. Born in Stockholm in 1796, the son of a German-born musician, Berwald enjoyed a varied career, never winning the position he hoped for in the musical establishment of the country. Born the year before Schubert, whom he outlived by forty years, he also outlived Mendelssohn, thirteen years his junior, by 21 years. The four symphonies of Berwald have a particular importance in the development of the symphony from its classical origins into the age of romanticism, with its freedom and innovation. His Sinfonie naïve, a title he later wisely abandoned, the fourth, was completed in 1845 and first performed in 1878, ten years after the composer's death. The Adagio, in D major, has a rustic calm about it at the outset, with the opening material appearing also in an organ duet version from the national tone-picture A Rustic Wedding, at one time a vehicle for the Swedish nightingale, Jenny Lind.

Spartacus, the Thracian gladiator who led a slave rebellion against Rome in 73 B.C., was, after some two years, defeated by Crassus, his remaining followers then eliminated by Pompey. For Karl Marx he offered an example of heroic rebellion by the proletarian, however unsuccessful the outcome of his revolt, and for Soviet ideologues a suitable case for sympathetic treatment. The Armenian composer Avram Khachaturian wrote his ballet on the subject in 1954, providing a fine romantic Adagio, in the spirit of early Rachmaninov, for Spartacus and his wife Phrygia, the latter sold as a slave to the household of Crassus. The couple are re-united, to be separated only by the defeat and death of Spartacus with which the ballet ends.

The beautiful Adagietto from Gustav Mahler's Fifth Symphony is a contrast to the overt drama of Spartacus, with its obvious romantic appeal. At the height of his career, now as conductor at the Vienna Court Opera, Mahler began the symphony during summer holidays in 1901, the year of his marriage to the young Alma Schindler. He completed the work the following year. Scored for strings and harp, the Adagietto, familiar also from its use in Visconti's film of Thomas Mann's novelle Death in Venice, is a reflection of the words of the poet Riickert that he set in the same year, Ich bin der Welt abhanden gekommen:

I am dead to the world.
I live alone in my heaven,
in my words, in my song.